Automated work stations are known which carry out the operations of fitting and welding together shaped metal sheets and the like to form monolithic structures, such such as, example the bodies of motor vehicles, driver's cabs of trucks and other structures, as for electrical household appliances.
These work stations make use of elements, called "configurations" which consist of a frame supporting centering, clamping and, if necessary, also welding means disposed so as to be able to secure and weld a particular conformation of metal sheet.
The type and arrangement of the devices supported by the configurators depends upon the particular production that the station is used for.
For this reason, in the known technique, in order to make the work stations more flexible, the configurators were made uncoupleable and replaceable these to a small automatic magazine inside the welding station that enables them to adapt quite rapidly to a different model. For example, in the case of the manufacture of car bodies this makes it possible to handle different models, or types of car on the same production line.
In order to make the system even more flexible, work stations have been constructed comprising means for moving the configurators which means are capable of automatically replacing them by taking them from an additional magazine, outside the station, thus making it possible to alternate different models on the production line; models to each of which is associated a particular pair of configurators (in general, the work requires one configurator for each side of the line).
These solutions, however, have various disadvantages such as large dimensions, especially with regard to the magazine, and considerable structural complexity, since they have to move considerable loads (both in weight and in size) and position them with the utmost precision with a relative mechanical apparatus which is always extremely complex and represents an important part of the station. Moreover, in said known systems, moving the configurators, both within the machine, and to and from the additional external magazine, can take a considerable length of time and slow up the production line unless prepositioning is possible.
Furthermore, the intrinsic complexity of the system bears very heavily upon both construction and maintenance costs. The general scope of this invention is to obviate the foregoing drawbacks by means of an automatic system for fitting together shaped metal sheets and the like which, although being able to handle different models of manufactured articles, is structurally simple and compact and offers the possibility of rapidly switching from one model to another and of achieving high output rates.